Rietberg

Rietberg was an imperial county on the upper Ems in Westphalia, between the bishoprics of Paderborn and Münster. In 1337 it was ruled by Count Conrad of the Rietberg family.

Rietberg retained its own laws, militia and coinage, striking money into the 17th century. In 1699 the heiress Maria Ernestine of East Frisia married Maximilian Ulrich von Kaunitz, bringing the county to his family. It was mediatised to the Kingdom of Westphalia in 1807 and passed to Prussia after that kingdom collapsed in 1813.